The invention relates to a method for connecting winding materials to terminal elements, in particular for connecting wire ends insulated with highly heat-resistant lacquer to terminal pins, the winding material being wound around a terminal element and being connected to the terminal element mechanically and electrically at at least one connection point by the application of energy. In addition, the invention also relates to the associated device for carrying out the method using a winding device comprising wire-feed device and a winding nozzle.
A great variety of methods have hitherto been used in practice for connecting winding ends of winding materials, particularly of heat-resistant and highly heat-resistant lacquered wires: if the lacquer on the winding material end has been stripped, soldering or welding methods can advantageously be used. In this connection, both soft soldering and hard soldering are suitable as soldering methods, and for example, arc welding, electron-beam (EB) welding, resistance welding, laser welding or ultrasonic welding are suitable as welding methods. Since, however, the stripping of the lacquer implies an additional operation, efforts are being made, within the framework of an integrated manufacture, to achieve a connection without prior stripping. In the case of heat-resistant lacquered wires, on the one hand, a specific high-temperature soft soldering or, alternatively, the welding methods already mentioned are suitable for this purpose.
Because of the application of energy with comparatively high intensities necessary in this process, additional metallic elements such as, for example, sleeves, straps or cover plates normally have to be used as aids for this purpose. For ultrasonic welding, in particular, it is also already known from European reference EP-B-0 200 014 to weld, in a single method step, a wire to a connecting element by ultrasonic welding by breaking up the insulation layer and deforming the cross section, the connection region then immediately being enclosed with a drop of a fast-curing organic or inorganic adhesive.
The latter method is suitable, in particular, for thin lacquer-insulated wires if a planar terminal element is available and the energy can be applied in a localized manner. It is used, for example, to produce electronic components for the SMD technology. The known method is less suitable for connecting winding materials in the automated production of coils if winding material and/or terminal element perform rapid movements.